PORTLAND – A hundred thousand words.

That’s what “In Our Time: The World as Seen by Magnum Photographers” is worth. The show, which is on view through June 4 at the Portland Museum of Art, includes 100 images from members of the exclusive agency. This is the first stop for the traveling exhibition, which was organized by the George Eastman House.

From Dennis Stock’s iconic portrait of James Dean in Times Square to Henri Cartier-Bresson’s photograph of the sea of people attending Gandhi’s funeral, each image in the exhibit eloquently captures a moment of 20th century history.

PMA curator Susan Danly arranged the exhibit chronologically, beginning in the 1930s with photographs by artist-turned-photojournalist Cartier-Bresson, who, along with David “Chim” Seymour, Robert Capa and Werner Bischof, founded the collective in 1947.

“By starting with him, [the viewer is] reminded there’s always an aesthetic eye behind the framing of these pictures,” Danly said.

Cartier-Bresson coined the phrase “the decisive moment” – the time at which an image is at its most resonant – a second before or after, and the shot is gone. It takes a good photographer to know the difference. But a good eye isn’t the only criterion for membership in Magnum.

Its founders had two goals in mind: to keep the independent spirit of photography alive by allowing members to work outside the confines of magazine and newspaper journalism; and to allow the photographers to both own the copyright to their work and control its placement. This freed the foursome to cover parts of the world that interested them, thus their work was driven by their own curiosity rather than an assignment sheet.

“They have a viewpoint, they have a story to tell, and all of their photos tell that story,” Danly said. “This isn’t merely a record of something, it has an implication.”

Though Magnum now has more than 100 members who range in age from 26 to 92, that tradition continues.

Curiosity led a young Susan Meiselas to spend three years documenting carnival strippers – a common sideshow at New England’s state fairs in the 1970s. That project took her to Maine, and one of the photographs from the resulting book, “Carnival Strippers,” is on view in Portland.

“The economic choices for women were limited and I was struck by the public sexuality, which of course now seems almost innocent,” Meiselas said Saturday from San Francisco. “All the participants were quite frank about their desires. I wanted readers to hear their views and reflect on the ‘girl show’ through the images, as well.”

Though the Eastman House chose the images included in the exhibit, Danly chose their placement, and her juxtapositions only enhance the power of the photographs. For example, she paired Meiselas’ “Carnival Strippers, Essex Junction, Vermont,” which is framed to show only breasts and bellies, with Inge Morath’s “Bas-Relief of a Buddha, Hangzhou, China.”

“It’s like storytelling to me,” Danly said. “How do you get a museum-goer to move from one picture to the next? What story do you want to tell?”

The stories of “In Our Time” are told in black and white, and they embody some of the most important events of the 20th century, from the fight for civil rights in the 1960s to the rise of Arab nationalism in the 1970s.

In addition to her “Carnival Strippers” piece, one of Meiselas’ images from her coverage of El Salvador’s civil war is on view. The photograph, taken in 1980, depicts the shadows of a line of bus passengers, hands over their heads, as soldiers conduct a search.

“This is one of the images that is burned into my memory, along with others of bodies dumped on the side of roads, victims of the death squads,” Meiselas said. “The brutality of that period is hard to forget.”

Though the latest photograph in the show was taken in 1987, the politics and issues are still relevant today.

“I knew it would have some resonance to political events,” Danly said. “But I didn’t select the pictures – I think that’s a testament to Magnum photographers.”

Though “In Our Time” shows the many faces of war, conflict and political unrest, it also has a lighter side. Magnum photographers have an affinity for dogs, and Wayne Miller’s “Westminster Dog Show” – of a wide-eyed lap dog and its master – proves the adage that dogs and their owners look alike. And Eliot Erwitt’s “The ‘Kitchen Debate,’ Moscow, USSR, 1959” shows Nixon and Kruschev in a heated argument about appliances.

“Magnum photographers can take a very somber picture but they can also take a very funny picture,” Danly said. “I do hope people come away with a sense of humor about this.”

Related events: Photojournalist James Nachtwey, former Magnum photographer, 6:30 p.m. Monday, June 19, Holiday Inn by the Bay, Portland, free admission, call 775-6148, ext. 3227, to reserve seats; “Henri Cartier-Bresson: The Impassioned Eye,” film, 6 p.m. Friday, April 28, PMA auditorium, $5; an appreciation of others’ humanity with filmmaker Karen Shopsowitz, presented by Northeast Historic Film, 6-7:30 p.m. Friday, May 26, PMA auditorium, free.

In Our Time: The World As Seen by Magnum Photographers

When: Through June 4

Where: Portland Museum of Art

Hours: 10 a.m.-5 p.m. Saturday-Thursday; 10 a.m.-9 p.m Friday.

Admission: $8 for adults, $6 for senior and students, $2 for youth ages 6 to 17, free for children under 6.

Contact: 775-6148, www.portlandmuseum.org